1. Field of the Invention
The invention relates to chemical mechanical polishing equipment, and more particularly to apparatus of carrier in the chemical mechanical polishing equipment.
2. Description of the Prior Art
Fabrication of semiconductor integrated circuits (IC) is a complicated multi-step process creating microscope structures with various electrical properties to form a connected set of devices. As more layers are built up on the silicon wafer, problems caused by surface non-planarity become increasingly severe and can impact yield and chip performance. During the fabrication process, it may become necessary to remove excess material in a process referred to as planarization.
A common technique used to planarize the surface of a silicon wafer is CMP. CMP involves the use of a polishing pad affixed to a circular polishing table and a holder to hold the wafer face down against the rotating pad. A slurry containing abrasive and chemical additives are dispensed onto the polishing pad.
As depicted in FIG. 1, a CMP system 110 typically consists of a carrier module 120, a support module 130, a polishing pad module 140, and a conditioning module 150. Typically a polishing pad on the circular polishing table in the polishing pad module 140 is comprised of blown polyurethane with a felt surface layer containing many small pores to facilitate the flow of slurry to beneath the wafer being polished. The carrier module 120 provides the holder to hold the wafer face down against the rotating pad. Typically a retaining ring 125 in the carrier module 120 can prevent the wafer edge against contact with the polishing pad in a deformed shape.
On the other hand, the support module 130 comprises a rotation system 132, a pressure system 134 and a chemical system 136. The rotation system 132 is used for the rotation motion of the carrier module 120. The pressure system 134 is used for providing the down force of the carrier module 120 to keep the wafer in contact with the polishing pad. The chemical system 136 is responsible for supply of the slurry containing abrasive and chemical additives. Furthermore, the conditioning module 150 comprises a conditioning chemical system 154 and a robot system 155. The conditioning chemical system is responsible for the supply of the conditioning solution. The robot system 155 is used to the mechanical motion during conditioning process.
It is very important for the CMP system 110 to provide the smooth-changed and controllable polishing rate. However, the typical CMP system 110 only maintains the polishing rate in either ex-situ or non-real-time-in-situ pad conditioning, that is, the pad conditioning step can""t be simultaneously implemented with the polishing step. Such an architecture may not fulfill the further shrunk IC design and manufacture. On the other hand, there is occupied space for the conditioning module, that causes the higher consumption of the CMP system in a semiconductor manufacture factory.
It is an object of the present invention to provide apparatus of carrier and a system of chemical mechanical polishing. A retaining ring combined with the conditioning function can provide activating pad and polishing wafer real-in-situ.
It is another object of the present invention to provide apparatus of carrier and a system of chemical mechanical polishing. A retaining ring made of the material of the conventional conditioner can be controlled with independent rotation motion and down-force supply.
In the present invention, apparatus of carrier in chemical mechanical polishing equipment comprises a carrier module for holding a wafer face down. A retaining ring and conditioning module is coupled to the carrier module, which is used for protecting the wafer edge against contact with a polishing pad in a deformed shape and executing a conditioning of the polishing pad while the wafer is being polished. A first support module is coupled to the retaining ring and conditioning module, which is used for rotating, pressing down, and supplying conditioning chemicals for the retaining ring and conditioning module.